AVR-Chat

I have the same issue with a different board and build process.


I've done this on my ATMega8 board now, building the HEX file using make.

crystal 8Mhz


I put the F_CPU value in the makefile as well as the global.h file.

I program the ATMega8 board by way of ISP then unplug the programmer from the ISP header.

When I look at the signal, I get between 0.9 and 2.1ms (about)for a call for 5ms.

When I try 10ms delay, I get between 2 and 4ms delay.




An interesting note: 

When I call the microsecond delay I am solid!

_delay_us(333);

Whatever value I tell it to wait, it is exact!

:)



So milliseconds does not work but microseconds does....






--- In AVR-Chat@yahoogroups.com, John Samperi <samperi@...> wrote:
>
> At 03:26 PM 31/08/2012, you wrote:
> >2.  F_CPU is set correctly
> >#define F_CPU          7372800
> 
> But is this what you have in the project settings? _delay_ms is pretty
> accurate if it has the correct information.
> 
> Are you using your own makefile or the Studio generated one?
> 
> 
> 
> Regards
> 
> John Samperi
> 
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